1. Field of the Invention
The invention relates to a plate-link chain in particular for steplessly variable gear ratio, conical-disk transmissions, such as CVT transmissions, of which the individual chain links are formed from sets of plate links connected by articulation members, preferably as pairs of rocker members having rocker faces braced against each other and that are inserted into openings in the plate links. The invention also relates to a method for manufacturing such a chain.
2. Description of the Related Art
Such plate-link chains are known in the state of the art. Examples are DE 197 08 865 and the documents cited therein, EP 0 518 478 and EP 0 741 255.
In plate-link chains of those kinds, to increase the load carrying capacity after assembly of the plate links and rocker members in a straight strand and an open formation, a stretching process is carried out by applying substantial tension forces to the extended plate-link chain. In that way the contact areas of the plate links between the plate links and the rocker members of all plate links of a row are equally plastically deformed. By stretching in a straight strand there arises an equalized plastic deformation of the plate links in the contact areas, so that the plate links of one row of plate links are equally elongated over the width of the plate link or exhibit equal lengths. That has the disadvantage that when the plate-link chain is under load during operation of a steplessly adjustable transmission the chains do not exhibit optimal service life and performance capacity.
An object of the invention is to create a plate-link chain and a method for its manufacture which, relative to the plate-link chains of the state of the art particularly, withstand higher operating loads or, at equal loads, have a longer service life.